Inflatable apparatus for use in plugging a large diameter pipe

Abstract

An inflatable plug adapted to be inserted into a pipe and inflated so as to plug the pipe and form a water tight seal. The inflatable plug is comprised of an inflatable bag of flexible sheet material forming an elongated cylinder having opposite ends. The material at the opposite ends of the cylinder is pleated or folded and wrapped around cylinders. Metal collars are placed over the folded material and swaged so as to clamp the material in fluid tight relation against the cylinders.

I claim: 
     
       1. Apparatus for use in plugging a large diameter pipe for preventing flow of water through the large diameter pipe, the apparatus comprising: a locker adapted to house an elongated fire hose and an inflatable bag,   a hose having opposite ends, said hose being housed in said locker, one of said opposite ends being connected to a source of water pressure, and   an inflatable bag housed in said locker, said inflatable bag being adapted to be connected to the other of said opposite ends of said hose and being adapted to be removed from said locker and inserted into the large diameter pipe wherein said inflatable bag can be inflated in the large diameter pipe and maintained in an inflated state in the large diameter pipe so as to plug the large diameter pipe and form a water tight seal therein, the inflatable bag including opposite ends and a longitudinal axis, said inflatable bag being comprised of at least one large sheet of thin flexible fluid impermeable material, said large sheet of material including parallel edges, said edges being sealed together to form a fluid tight seam extending substantially parallel to said longitudinal axis, and said material forming a plurality of folds parallel to said longitudinal axis, and said inflatable bag being sufficiently flexible that when said inflatable bag is deflated, said inflatable bag can be freely folded in a direction transverse to said longitudinal axis, said plurality of folds at one of said opposite ends of said inflatable bag being wrapped around said longitudinal axis in a spiral configuration when viewed in cross sections generally perpendicular to said longitudinal axis, and a first collar surrounding the flexible material forming said plurality of folds spirally wrapped around said longitudinal axis at said one of said opposite ends, and clampingly engaging said flexible material to form a fluid closure at said one of said opposite ends, means for providing a connection between the other of said opposite ends of said hose and said inflatable bag, said means for providing a connection including a coupling, said plurality of folds at the opposite end of said inflatable bag being wrapped around the longitudinal axis in a spiral configuration when viewed in cross section generally perpendicular to said longitudinal axis, and a second collar surrounding said plurality of folds of material spirally wrapped around said longitudinal axis and forming said opposite end of said inflatable bag and clampingly engaging said flexible material forming said opposite end to form a fluid tight seal between said plurality of folds of flexible material and said coupling, and said elongated flexible bag having a diameter when said elongated flexible bag is inflated substantially larger than the diameter of said elongated flexible bag when said elongated flexible bag is deflated.